HR: 16:20h
AN: SM34A-01    [Abstracts]
TI: Solar wind interaction with Venus at solar minimum: Venus Express magnetic field observations
AU: * Zhang, T L
EM: tielong.zhang@oeaw.ac.at
AF: Space Research Institute, Schmiedlstrasse 6, Graz, Austria
AU: Delva, M
AF: Space Research Institute, Schmiedlstrasse 6, Graz, Austria
AU: Baumjohann, W
AF: Space Research Institute, Schmiedlstrasse 6, Graz, Austria
AU: Russell, C T
AF: Institute of Geophysics, University of California 405 Hilgard Ave, Los Angeles, CA 90095, United States
AU: Glassmeier, K H
AF: IGEP, TU Braunschweig, Germany
AU: Barabash, S
AF: Swedish Institute of Space Physics Swedish Institute of Space Physics, Kiruna, Sweden
AU: Balikhin, M
AF: University of Sheffield, Sheffield, United Kingdom
AU: Kudela, K
AF: Institute of Experimental Physics, Kosice, Slovakia (Slovak Republic)
AB: The launch of Venus Express provides a new opportunity to study the solar wind interaction with Venus. Although a wealth of knowledge about the interaction of Venus and the solar wind has been obtained from earlier missions, notably the long lasting PVO mission, Venus Express will greatly improve our view of the Venus plasma environment due to many unique characteristics of the mission such as the improved capability of the onboard instrumentation, the unique orbital trajectory and the solar minimum observations at a low altitude compared with PVO. It is the purpose of this paper to illustrate some of the new science obtained by the Venus Express. We find that the bow shock stands off from the planet a smaller distance than at solar maximum. On the dayside, the magnetic field piles up to form a magnetic barrier in the inner magnetosheath. This magnetic barrier, an induced magnetosphere on the dayside, acts as an obstacle to the solar wind in analog to the Earth's magnetosphere. The magnetic barrier is bounded by the ionopause at its lower boundary and a "magnetopause" at its upper boundary. Both ionopause and magnetopause extend to nightside. The magnetopause on the nightside separates the magnetosheath and magnetotail which is formed by the anchored, draped magnetic fields. In contrast to its unmagnetized state at solar maximum, the ionosphere appears to be completely magnetized and its upper boundary, the ionopause, significantly lowered. The magnetic draping configuration on the dayside becomes reverse draping on the night, forming a near toroidal magnetic field at low altitude.
DE: 2154 Planetary bow shocks
DE: 2724 Magnetopause and boundary layers
DE: 2780 Solar wind interactions with unmagnetized bodies
DE: 5440 Magnetic fields and magnetism
DE: 6295 Venus
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly